Control of carburetors for internal-combustion engines



Patented Apr. 2 7, 192,6.

UNITED STATES A 1,582,239- PATENT. OFFICE.

MARIUS JEAN-BAPTISTE BARBAROU, OF PARIS, FRANCE.

CONTROL OF CARBURETORS FOR INTERNAL-COMBUSTION ENGINES.

Application led February 23, 1924. *Seriall No. 694,805.

to be able to increase the compression in the engine according as theengine rises.`

'lhis increase of compression may be obtained by increasing the quantityof gas admitted. into the power cylinder per revolution of the engine,and this is done by acting on the throttle of 'the carburetor. But it isreadily understood that if in order t0 operate the engine at a highaltitude, the carburetor throttle is fully open, the full opening of thelatter must4 be prevented when the engine is working at mean or lowaltitudes, for the compression would then De much too high, and thiscould cause serious damage to the engine.

The present invention has for its object a control device for 'theautomatic regulation of the maximum opening of the throttle Of thecarburetor of an internal combustion engine, according to the altitudeat which the engine is working.l One feature of the device accordingtothe invention resides in that it comprises an elastic membrane Or likemember, subjected on oneiside to a predetermined constant pressure, andon the other side to the surrounding atmospheric pressure, said membranebeing operatively connected with oneujoint of the rod and link gearconnecting thepcontrol y member to the carburetor throttle, so astochange the angular position of said joint, and consequently to changethe angular po-v sition of said throttle, accordinv to the alti- "tudeat which the engine lis wor ing.

In the appended drawing which showsby way of example two forms ofconstruction of the carburetor control according to the invention:

Fi 1 is a diagrammatic vfrontV view of lone Orm of construction of thedevice; the

position of the elements for the maximum possible opening, in the case1n which the engine operates at the ground level is shown in full lines,and the position of the same elements for the maximum possible openingwhenthe engine operates at the maximum altitude for which the controlhas been dcsigned is shown in full and dotted lines.

Fig. 2 shows the position of the parts for the slow speed working of theengine when :on thel ground.

Fig. 3 is a section on A-A of Fig. 2. In the construction shown in Figs.1 to 3, the pipe 1, which supplies to the engine the gases coming-fromthe carburetor, carries a shaft 2 on which is movable the tlirottle 3.The throttle 3 is secured to a lever 4 to which is attached one end of alink 5 connected at its Otherend with one arm of a bell-crank lever 6`keyed to a shaft 7.

` To the other arm of the lever 6 is pivoted a piece or stud 8, in whichisslidably mount. ed one of the arms 9 of a ringlO, the other '7 Iandprovided with a stud 14 upon which .is mounted, through the medium of aballand-socket joint, the rod 15 connected to the control member withinreach ofthe driver] or pilot.

'The shaft 7 carries a piece 16 having an aperture 17 of theshapeillustrated. in the drawing and whose width is equal to the diameterof'the said shaft. This piece 16 carries a cincular hub 18 on which ismounted the ring 10. A rod 19 is secured at one end tothe piece 16,Awhile at the other said rod is attached to an elastic'diaphragm 20contained in a receptacle 21. This diaphragm 2O divides the receptacle21 into two chambers22 and 23; the chamber 22 isaconnected with ahermetically closed 'chamber 24 provided with a conduit 25 adapted toallow in the chamber 22 a pressure of a Welldeterniined value; theohaniber23 is open to the atmosphere. The diaphragm 20 is on theyOther-hand subjected to the action of a spring 26 which is properlyadjusted With respect to the pressure in the chamber 22,

so .as to only allow the motion of said dia'- phragm when the outsidepressure prevailing in the chamber 23 shall be below a stated value. l

The operation of the apparatus is as follows: To Open or close thecarburetor .throttle 3 the driver or pilot acts on the lever or likecontrol member, which is Within his reach. This action, through ,themedium of the rod 15 will cause the disc 13 to rotate. The latter,through the medium of the piece 12, will actuate the arm 11 of the ring10 which, when turning on the hub of the piece 16, will act by its arm 9on the piece 8 and will 'thus rotate the bell-crank lever 6 which,through the medium of the link 5 and the lever 4, will move thecarburetor throttle. If the pilot pulls on the rod-15 in the direc'-tion ot the arrow 15a, the disc 13 and the bent lever 6 arc rotated inthe direction ot the arrow 13, which causes the opening of the throttleof the carburetor in the direction ofthe arrows 3a.

If the engine is working at lo-W altitudes,

. the ring 10 is now in the position shown in full lines in Fig. 1 andthe maximum possible opening of the carburetor is the one illustrated;this openingfis limited according to the maximum stroke of the leverwhich is Within reach of the pilot.

But if the engine works at a higher altitude, the atmospheric pressurewill diminish, and in these conditions the diaphragm' 20- pushes the rod1 9, `and this causes the piece .16 to slide on the'shaft 7 and bringsit into the position shown in full and dotted lines in Fig. 1. It willbe readily noticed that in this movement the centre of the ring 10 comesto 27, and as the pilot or the driver has left his lever in the positionvof maximum opening, the disc 13 remains Xed but the bent lever 6 comesinto the position shown in -full and dotted`lines,.thusfurther openingthe carburetor throttle 3. a being the angle of rotation of the piece 8i. e. of the disc 13, fromthe position shown in Fig. 2, to the positionshown in Fig. 1 when the center of the ring 10 registers- With thecenter of the disc 13, and being the angle of rotation of the piece 8corresponding to a rotation of same magnitude a of the disc 13 when thecenter of the ring 10 is at 27, is

- obviously greater than a. It is thus ob'- served that for a givenmovement of the conductors hand. lever,""correspondin0 to an angle 'ofrotation a of the disc 13, tilie angle of rotation of the lever 6 is a,in case the engine is working on the ground, andl is lin the case inwhich the engine is Working 'at a, higher 4altitude i. e. when thecenter of the ring 10 is at the point 27.

To bring back the engine to slow speed, it sufices to act upon the rod15 in the contrary direction tothe arrow 15a; the disc 13 will turn inthe contrary direction to 13a; the arm 11 coming into the horizontalposition (Figs. 2 and 3) the position of the bent lever 6 is suoli thatthe throttle 3 will only give passage to exactly the` amount of gasnecessary to keep up the slow speed working. Since at this time the arm9 is also horizontal. whatever may be the outer air pressure, that is tosay whatever may be the position oi? the piece 1G, the earluu'etorthrottle will have the same position and will remain closed. The 'actionof the manometric receptacle-21 will be manifested according as thepilot acts upon the control device to open the carburetor throttle.

Various constructional modifications may obviously be brought to theabove described device without departing from the spirit ot theinvention.

Having now.described my invention what I claim as new and desire tosecure by Letters Patent is: l

A conti-olf gear for the carburetor of an internal combustion enginecomprising a control member operated by the operator, a' rod and linkgear embodying two swinging arms respectively connected to said controlmember and to the carburetor throttle, an intermediate member upon whichsaid arms are jointed, a shaft on which said two swing-V ing arms andsaidintermediate member are mounted and whereon said intermediate memberis adapted to slide transversely with respect to said shaft,'an elasticmembrane subjected on one face toa predetermined constant pressure andon the other face to the surrounding atmospheric pressure and meansoperatively connecting said elastic membrane to said intermediate memberaud adapted to transversely displace said intermediate member andwhereby the angular osition of said arm connected -to the car-

